RCAAP Repository

No summary/description provided

No summary/description provided

Orbit error is one of the largest sources of uncertainty in studies of ocean dynamics using satellite altimeters. The sensitivity of GEOSAT mesoscale ocean variability estimates to altimeter orbit precision in the SW Atlantic is analyzed using three GEOSAT data sets derived from different orbit estimation methods: (a) the original GDR data set, which has the lowest orbit precision, (b) the GEM-T2 set, constructed from a much more precise orbital model, and (c) the Sirkes-Wunsch data set, derived from additional spectral analysis of the GEM-T2 data set. Differences among the data sets are investigated for two tracks in dynamically dissimilar regimes of the Southwestern Atlantic Ocean, by comparing: (a) distinctive features of the average power density spectra of the sea height residuals and (b) space-time diagrams of sea height residuals. The variability estimates produced by the three data sets are extremely similar in both regimes after removal of the time-dependent component of the orbit error using a quadratic fit. Our results indicate that altimeter orbit precision with appropriate processing plays only a minor role in studies of mesoscale ocean variability.

The present study investigates the modern sedimentation pattern in Ubatuba coastal region, State of São Paulo, through the identification of the main mechanisms of input and remobilization of sediments and through the definition of their temporal variations. The study area covers five bays: Ubatuba Bay, Toninhas Bay, Flamengo Bay, Fortaleza Bay and Mar Virado Bay. Results show the existence of dynamic conditions for remobilization of fine sandy sediments previously and during the passage of cold fronts over the area, and for the transport of suspended material during the entire period of the study. Sedimentation patterns unique to each bay, occurring as function of the physiographic and hydrodynamic characteristics of each bay are also identified. Besides sediment remobilization, input of terrigenous materials from the continental area is also evaluated.

Nitrate reductase (NR) activity was studied in the marine diatom Biddulphia longicruris. During 24 hours of sampling, NR activity was found during day time and in the transition day-night. Nitrite anions, the product of nitrate reduction, was released by the cells at the times NR was active, and accumulated in the culture medium. Whenever the cultures of B. longicmris were submitted to nitrogen deprivation, NR activity could not be detected. In vitro determination of KM values for NR using nitrate or NADH were respectively 50//M and 80 /*M. Temperature and pH dependence of NR activity were also determined for this organism.

Mean and specific oxygen consumption and ammonia excretion were measured at 0ºC and 3ºC, in the Antarctic amphipod Waldeckia obesa collected in Admiralty Bay, King George Island, Antarctica. Experiments were carried out at the Brazilian Antarctic Station "Comandante Ferraz" and at the Laboratory of Polar Ecology of the Oceanographic Institute of São Paulo University. Individuals ranging from 120 mg to 620 mg and from 40 mg to 690 mg were employed in experiments at 0ºC and 3ºC, respectively. Within this range of weight, mean oxygen consumption varied from 2.22µ1/h to 10.81µ1/h and specific consumption from 0.011µ 1/mg/h to 0.018µ 1/mg/h, at 0ºC. At 3ºC, mean oxygen consumption varied from 1.83 µ1/h to 14.9µi/h and specific consumption from 0.033µ1/mg/h to 0.022µ1/mg/h. Q10 value calculated from average oxygen consumption was 6.95. Mean ammonia excretion, at 0ºC, varied from 13.84 ng.at/h to 55.34 ng.at/h and specific excretion from 0.090 ng.at/mg/h to 0.042 ng.at/mg/h. At 3ºC, mean ammonia excretion varied from 5.11 ng.at/h to 38.33 ng.at/h and specific excretion from 0.088 ng.at/mg/h to 0.059 ng.at/mg/h. 0:N ratio indicates that a mixture of protein and lipids is utilized for catabolism. At 3ºC, however, there is a tendency to increase the lipid contribution for the substrate. Oxygen consumption of Waldeckia obesa at 0ºC is very low and is in accordance with the values reported by some other authors. These data and others recent results found in the literature indicate the fragility of the "metabolic cold adaptation" hypothesis, that assumes that marine Antarctic ectotherms have high metabolic rates, as an evolutive adaptation to low temperatures. Oxygen consumption and ammonia excretion data could be extrapolated to populational parameters giving support for the studies on the ecological role of these animals in their ecosystem.

This study analyses the composition, relative abundance, seasonal patterns and community structure indices of surf-zone fishes at Ilha Comprida, Santos and São Vicente, and Vermelha do Sul and Félix, South, Central and North regions, respectively, of São Paulo State. A total of 54,384 individuals of 99 species was captured, the highest values of relative abundance, number of species, genera, families and exclusive taxa were observed at Central Region, and the lowest ones at South Region. The relative abundance and diversity indices showed the same pattern for all regions, with higher values in summer-fall (higher values of water and air temperature and rainfall and lower salinity), and lower ones in winter-spring (lower values of water and air temperature and rainfall, and higher salinity). Faunal similarity increased from species to family, being lower between Central and North and higher between South and Central regions.

Foram analisados dados de correntes e de propriedades hidrográficas amostradas durante três ciclos completos de maré, em dezembro de 1991. O máximo valor da componente longitudinal da velocidade da corrente variou, para as condições de enchente e de vazante, de 50 a -100 cm/s com esses extremos precedendo de 1,0 a 1,5 horas a ocorrência dos instantes de maré alta e baixa, respectivamente. A componente transversal de velocidade mostrou que a circulação secundária predominava na direção leste com núcleos de máxima de até 30 cm/s em profundidades médias, enquanto que no sentido oposto (para oeste) essa componente apresentou valores máximos próximos a -10 cm/s na camada de superfície. A variabilidade da salinidade indicou uma quase homogeneidade vertical e durante a enchente o seu máximo (34,5-35,0 %o) precede a maré alta com uma defasagem de 1,0-2,0 horas. Entretanto, durante a vazante, a maré baixa precede o mínimo de salinidade (29,5-30,5 %o) com defasagens entre 2 e 3 horas. Não obstante a região estudada ser parte de um complexo sistema estuarino de planície costeira, o extremo sul do Mar de Cananéia foi classificado, de acordo com o Diagrama Estratificação-circulação, como parcialmente misturado e fracamente estratificado (Tipo 2a). O movimento resultante reverte a 2,5 m de profundidade e quase 100% do fluxo de sal estuário acima é devido a difusão turbulenta.

No summary/description provided

This paper presents the taxonomic results regarding the Chaetognatha collected during a voyage to the oceanic island of Trindade made in 1950. Collects were done at different stations around the island and in the waters above banks between the island and the continent. Seven different species were collected, 5 of which belong to the genus Sagitta: 8. bipunctata, 8. enflata, 8. friderici, 8. hexaptera, 8. serratodentata, one is recognized as a new species of the genus Pterosagitta: Pt. besnardi, and finally the last is Krohnitta subtilis. Descriptions and drawings are presented of the species, as well as records of what is known of their habits and of the environments which they select. The new species, Pterosagitta besnardi, the second known of this genus, is as a whole similar to its elder: Pt. draco; but differs from it in some essential points. Pt. besnardi is shorter, its caudal segment is proportionately shorter, it has a smaller number of teeth and hooks, the hook's sheath has no crest, it has intestinal diverticula, its receptacula are extremely large and have a clavate shape and, finally its vesiculae are short and oval. This work was done aiming at a better knowledge of the Chaetognathous fauna of the western south Atlantic and for this purpose more work is being prepared dealing with the coastal species. Random informations are being pieced together in the hope of gathering in the near future enough material to establish some useful indicator among the species of this group that might be efficiently used for practical purposes.

This is a preliminary study of the wave action over the continental shelf of the State of S. Paulo, Chart I figures a theorical 180 m. long wave as would be produced by an eastern polar anticyclone. The waves will strike the coast at right angles with a slight divergence along the whole coast of the State; reaching a maximum at Santos and a minimum at Cananeia. Chart II, figures the waves, incidence at Cananeia; it can be pointed out that the island of Bom Abrigo offers no protection against a wave coming from the east and that this wave penetrates easily along the pass leading to the inland waters of the region of Cananeia.

No presente trabalho o autor refere o achado de uma planta coletada uma única vez no litoral sul do Brasil. Além de uma nova descrição é também proposta uma nova combinação em conformidade com a moderna nomenclatura ficológica.

The return voyage from the Island of Trindade (Besnard, W., 1951, p. 37-48) to Rio de Janeiro was made on board of a trawling boat, "Vega", and the established route was through the series of banks that occur between the continent and the group of islands Trindade and Martim Vaz. The banks are accurately placed on the map and the deepness of the ocean above them, correctly stated. Dredgings, due to lack of time and inappropriate gear available on board, brought back only samples comparable to those of the insular platform of the island of Trindade, more similar to the collections made nearer the island, and gradually differing from them on the banks located closer to the continent. As is shown in the accompanying schematieal section, the submarine profile is extremely irregular, there being instances of falls of over 2.000 meters in the distance of a few meters. It seems, therefore, reasonable to imagine that there is, between the continent and the island a series of mountains and ridges possibly of eruptive nature. However, the schema is necessarily very incomplete due to the scarcity of the soundings. The voyage was altogether much too short for more than a quick glance, that produced enough material to show that it is an interesting region from several points of view and worth of a more detailed study.

In this "previous note" we are presenting the results obtained by our Researches and referring to the waters of junction around the Island of Casca, located between the Trapandé Bay and the Canal of Ararapira, in the Lagoon Region of Cananéia, in the southern part of the S. Paulo State, Brazil. This note is a continuation of the physical and chemical researches of the Hydrographie System of the Cananéia Lagoon Region. In the Bull. Inst. Paulista de Oceanografia, vol. I, fase. I, pág. 45, 1950, we present the first results of the works carried out in the region. "We give the situation and description of the Island of Casca 's region, situated approximately near the crossing of lat. 25º4' S with long. 48º3'30" W; a bathymétrie study and the results obtained by our preliminary Technical Researches. We referred to the water samples collected from 8-12-48 to 27-10-49, the results of which are shown on table I and II. We discussed all these results, showing some graphics and comparing them with the physical and chemical properties of the surrounding waters - Table II and IIa. We constructed a T-S diagram in order to make evident the particularities which may exist. We discussed the origin of the predominating waters of the Island of Casca's region of junction, having made a tentative essay of dynamics. The previous and undermentioned conclusions will be dully fitted of with the corresponding instruments: 1) As the region under observation has several sand banks the channels leading to Ararapira may suffer or not some modifications; 2) The variation of salinity is of the lagoon type, suffering the influence of tidal currents and the continental contingents; 3) The predominating waters of the region come, first during ebb from the Ararapira channel and second during high tide the superficial layers come in the Bay from the entrance of the region, since the entrance is blocked by the tidal flood, then by the rising of the water level, they enter into the region of junction; 4) The fall of the dissolved oxygen could not be explained, due to the complexity of the interfering factors, and stilJL depends on future studies; 5) The T-S diagram put in evidence the periods of greater or smaller influence of the continental contingents which reach the locality in the months of January, February, March and June, July and August and shows the harmonic variation of the salinity between waters of surface and depth.

In this paper are recorded 27 different species of Foraminifera collected along the coast of the State of São Paulo. The specimens were collected mainly at six points: "Rabo Azedo" beach in the Island of São Sebastião; "Flexeiras" beach, on the continent, near to the town of São Sebastião; beaches of "Ponta da Praia" and "Boqueirão" in the Bay of Santos; "Itararé" beach at São Vicente and "Praia de Fora", the beach of the "Ilha Comprida" (Long Island) at Cananéia. Collects were also effected in the channel of São Sebastião and at places near Caraguatatuba and Ubatuba, at spots located at the entrance of the bar of Cananéia and near the islands "Bom Abrigo", "Vitória" and 'Anchieta". Dredgings were done at depths varying from 0.80 to 12 meters. Of the 27 species recorded until now, 21 are from the northern coast of the State, 3 of which are present also in the central region (Santos and São Vicente) ; 6 species are from the southern coast of the State. The richest collects were from the northern litoral, especially so at the beach of "Flexeira'. The beach of Itararé although poorer in abundance produced a varied and most interesting material. In what concerns the genera represented by the greater number of species, are in first place Quinqueloculina and Discorbis, followed by Bolivina. Next comes Lagena with up to now only two species. The remaining 14 genera are represented by only one species. The authors studied the group only under an entirely taxonomic point of view to know which are the commonest species that occur on the coast of the State; they intend later to pursue biological and ecological researches in the group. Researches are being effected to study the occurence of certain forms in the different seasons, their distribution, both in the planctonic and sessil stage, on the beaches and bottom deposits, aiming at discovering their penetration and distribution in brackish and fresh waters of the littoral region of the State.

No summary/description provided

Trata-se aqui de um estágio post-larvar de Acanthurus hepatus (L), obtido na Ilha da Trindade (praia das Tartarugas). O autor compara esse exemplar com o que foi descrito por Breder Jr., em 1925 e proveniente de Glover Reef, ao largo do Yucatan.

No summary/description provided

No summary/description provided

This paper deals with the occurrence of Copepods in the Bay of Santos (State of São Paulo, Brazil) and its surroundings. During 1934-1945 the author collected plankton samples from that region not only to study its various components but especially to test its distribution in the contents of fish's stomachs. Thus, 1.136 samples were gathered, mostly from surface waters, since only 18.6% from intermediary and 8.8% from deep waters. According to the available literature, up to 1939, no important account had been given on the Copepoda from the coast of São Paulo and few works deal with this order from the Brazilian coast in general. Among them Van Douwe (1911; 1912), Wright (1927; 1935; 1936; 1936a; 1937), Kiefer (1935; 1936a; 1936&;) Chappuis (1936), Marsh (1933) and Schubart (1938-1942) who referred to some specimens from the north of Brazil. However, in all these works only brackish and fresh water specimens were considered. Later on, Oliveira (1945-1947) while carrying out researches on the micro crustácea from Guanabara Bay, presented interesting studies on marine species. A list is given of the commonest species collected and the author arrived to the following conclusions: a) excepting the genus Oithona, Paracalanus, Euterpina, Corycaeus and in certain months Acartia that, generally were found throughout the year, there was a great variation of species in the region investigated. b) In a general way, the author could not find that strict subdivision proposed by some authors who proved the existance of an absolute characteristical fauna on the surface, another intermediary one and still a bathipelagial one. This was due, perhaps, to the irregular catches and to the methods employed which could only be improved after 1947. c) Bright light did not cause the accumulation of organisms on the surface, excepting, obviously, the night catches; quite rich catches were made in misty days. d) Winds of high and medium speed had no great effect on the distribution of macroplankton while the rain seemed to help the concentration of Copepods on the surface, at least during the day; strong winds as well heavy rains drawn the plankton deeper down. e) The temperature influentiated the occurrence of material though slight changes had no great effect. f) As it was expected the zooplankton from the Bay of Santos presented the same characteristics as that from the open sea, though it proved to be poorer in quality and concerning some species, reacher in quantity. Some general considerations are made regarding the impure and contaminated water of a large city like Santos. While studying the research methods, the author gives slight references to the migration observed and to geographical distribution of some species.